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Wednesday, December 20, 2017

It has been a very busy summer, indeed. So busy that I have ended up writing this blogpost in December...

CES ringing (SYLVIA project) has revealed a quite good breeding season for many species. Early and abundant spring rainfall provided a food for many passerine species and no strong rain episodes occurred during the main incubation period, which is usually a potential cause for breeding failure. By mid-May some of the early species had already chicks in regular numbers, and June is the best time for all the species, with fledgings from the latest breeding species and, usually, second broods of the sedentary fellows.

Juvenile (EURING 3) Western Bonelli's Warbler (Phylloscopusbonelli). They arrive slightly earlier, mostly during April, andchicks are flying between late June and early July. They also leavethe breeding grounds between August and September.

Breeding Common Nightingales (Luscinia megarhynchos) start the postnuptial complete moult shortly after chicks fledge. The moult is also quite quick, with several primariesdropped at the same time. They will leave the breeding groundsalso during August and early September and they have to be ready for that!

Juvenile Lesser Spotted Woodpecker (Dendrocpos minor).I had never seen one with this greenish tinge on the face andunderparts!

Adult (EURING 4) Turtle Dove (Streptopelia turtur).

Juvenile (EURING 3) Rock Bunting (Emberiza cia).

At my main ringing station, L'Aiguamoll de la Bòbila, it was very nice to recover the breeding of Great Reed Warblers (Acrocephalus arundinaceus). Last year, since the wetland was dry during the whole spring and summer, there was only a brief sighting of a singing male after some little rain in June; but they never bred. This year, interestingly, two breeding pairs succeeded! Thanks to the ringing activities, both males and one of the females were already ringed from 2014 and 2015, which is quite interesting, since only one of these birds came last year, but they have all returned and succeeded this season!

A returning breeding female Great Reed Warbler from 2015!

Some interesting birds were caught in my main ringing station, L'Aiguamoll de la Bòbila, where I have already ringed more than 1000 birds this year.

Male Bee-eater (Merops apiaster).

Juvenile (EURING 3) Hoopoe (Upupa epops).

Juvenile (EURING 3) Wryneck (Jynx torquilla). Interestingly,this species is not breeding in the area, so this juvenile in mostlyjuvenile plumage caught in mid-July was clearly on juveniledispersion. As you can see, it's in the middle of the typicalwoodpecker postjuvenile moult involving primaries.

To compare with the previous one, this breeding individualfrom the SYLVIA station in La Corbatera was also on primarymoult in mid-July. It was aged as a 2cy (EURING 5) on thepattern of the unmoulted primary coverts in the previous moult.

Talking about woodpeckers, this year we also had a breedingpair of Green Woodpeckers (Picus viridis) at La Bòbila,and this was the female. Aged as an adult (EURING 6) due tothe all moulted wing except some central primary coverts,which seemingly happens regularly in adults of this species.

Working on the mountains with alpine species is always a delight, especially during the hot summer, when it's always very refreshing to be up there. One more year, we worked with breeding Northern Wheatears (Oenanthe oenanthe) in the same two areas we have been surveying in the past. Finally, we have started using colour rings with this birds, which will allow us to keep a better track of the returning individuals - which so far have been very few! Seemingly they do not return to the exact same breeding spots every season, so it's quite hard to detect them again when the habitat is so extensive.

It was also about wheatears when we went to some areas in the central part of Catalunya to target Black-eared Wheatears (Oenanthe hispanica), in collaboration with Reto Burri and José Luis Copete. The wheatears themselves are very nice birds!

Black-eared Wheatear in its typical open habitat.

Adult (EURING 6) male, black-throated morph.

Adult (EURING 6) male, white-throated morph.

But it was also a good opportunity to get experience with other typical species on this open habitats.

Tawny Pipit (Anthus campestris).

Woodchat Shrike (Lanius senator).

Western Orphean Warbler (Sylvia hortensis).

Ortolan Bunting (Emberiza hortulana).

An intense summer, with a lot of ringing, a lot of interesting data gathered and picture documentation... but too few time to put everything in order!!

Sunday, October 15, 2017

Millions, literally, of migratory birds fly over the Falsterbo peninsula every autumn. Its geographic position fits in what could be defined as a migration 'bottleneck', that Scandinavian birds use to shorten the sea-crossing from the southernmost parts of Sweden to Denmark or Poland, crossing the Baltic Sea. For anyone with a little passion for birds, a good day at Falsterbo is a truly astonishing experience.

The video above is representative of some minutes on a rather 'normal' September day at Falsterbo. It was recorded this last 16th of September, and you may recognize several passerines calling while actively migrating.

At the very start of the season, by late July, Acrocephalus species are already on the move, especially Sedge Warblers (A.schoenobaenus) but also the first migrant Reed Warblers (Acrocephalus scirpaceus). As soon as August starts more and more species finishes their moults (if they have any) and start their journeys south. As shown above, passerines migration reaches amazing numbers though August and September, when they are mainly Tree Pipits (Anthus trivialis), Yellow Wagtails (Motacilla flava), White Wagtails (Motacilla alba), Barn Swallows (Hirundo rustica), Sand Martins (Riparia riparia) and many other species. During September, Meadow Pipits (Anthus pratensis) will start dominating and finches will take over too, Song Thrushes (Turdus philomelos), Dunnocks (Prunella modularis), Goldcrests (Regulus regulus), Blue Tits (Cyanistes caeruleus) and with hundreds and hundreds of Chaffinches (Fringilla coelebs), Bramblings (Fringilla montifringilla), Siskins (Carduelis spinus) and other species like Reed Buntings (Emberiza schoeniclus) move on on daytime.

Chaffinch (Fringilla coelebs) and Woodlark (Lululla arborea).

Irruptive species are every year, the biggest change. This year it was a very good season for Crossbills (Loxia curvirostra), also some Two-barred (Loxia leucoptera) on the beggining of the season and very good numbers of Parrot (Loxia pytyopsittacus) during October!

Migrating Common Crossbills (Loxia curvirostra).

Raptors are also a big attraction to Falsterbo. Big numbers of Honey Buzzards (Pernis apivorus) can be seen during August, and then they are replaced by thousands of Common Buzzards (Buteo buteo) during September and October. Red Kites (Milvus milvus) are common migrants too, such as Marsh Harriers (Circus aeruginosus), but Hen (Circus cyaneus), Montagu's (Circus pygargus) and Pallid Harriers (Circus macrourus) also occur regularly through the season. Also worth mentioning the Black Kites (Milvus migrans), which are also uncommon but regular migrants over the peninsula. Eagles are always special, and usually, if any Eagle is wandering around southern Sweden it will eventually show up over the Falsterbo peninsula. Lesser Spotted Eagles (Aquila pomarina) are probably the more regular species, but Greater Spotted Eagles (Aquila clanga) also appear, and also eventual Steppe Eagles (Aquila nipalensis). Not to mention the regular White-tailed Eagles (Haliaeetus albicilla) or the Ospreys (Pandion haliaetus), which both occur regularly, especially the latter.

Variability within Honey Buzzards. Bottom right is a first-year, therest are all adults, sexes mixed.

The variation among Common Buzzards is also great! 'Scandinavian'/'white' Buzzards are regularly seen. They areso beautiful!

In terms of numbers, it's really shocking the large amount of Sparrowhawks (Accipiter nisus), that easily reach hundreds of individuals per day, and totals usually taking over 20.000 individuals each season. Falcons are less abundant, but also regular in good numbers, such as Hobbies (Falco subbuteo), Peregrines (Falco peregrinus), Common Kestrels (Falco tinnunculus) and Merlins (Falco columbarius).

Sparrowhawks are very common...

First-year Hobby (Falco subbuteo)

So common that they can pass even between your tripod legs!

Looking at the beaches, sandbars and pools close to the shore, good numbers of ducks and waders stop to feed and rest. At the beginning of the season, by late July and early August, hundreds of Terns (mainly Sandwich Sterna sandvicensis, Common Sterna hirundo, Arctic Sterna paradisaea) and waders, such as Red Knots (Calidris canutus),Bar-tailed Godwits (Limosa lapponica) and Oystercatchers (Haematopus ostralegus) are seen in rather big numbers. Dunlins (Calidris alpina) are also very common, peaking during August, and several more species appear in big numbers.

Revlarna packed with birds: waders, gulls, terns and ducks.

First-year Sanderlings (Calidris alba).

Wildfowl is also very abundant, with hundreds of Northern Pintails (Anas acuta), Northern Shovelers (Anas clypeata), Common Teals (Anas crecca), Mallards (Anas platyrhynchos) and thousands of Eurasian Wigeons (Anas penelope) gathering during September and October. Swans also gather in big numbers, especially Mute Swans (Cygnus olor), but Whooper (Cygnus cygnus) and Bewick's (C.columbianus) also occur. Geese are also very very common, and leaving apart the big flocks of Greylag (Anser anser) and local Canada Goose (Branta canadensis), there is a lot of migration of Barnacle (Branta leucopsis), Brent (Branta bernicla), Greater White-fronted (Anser albifrons) and Bean Geese (Anser fabalis). Common Cranes (Grus grus) are also seen in hundreds on migration between the end of September and beginning of October. Seawatching provides also big numbers of Common and Velvet Scoter (Melanitta nigra & Melanitta fusca), thousands of Common Eider (Somateria mollisima), numerous Black-throated (Gavia arctica) and Red-throated Divers (Gavia stellata), and much more...

Migrating Barnacles over the Flommen reedbeds. The species has increaseddrastically in the last decades in Southern Sweden!

Migrating Greater White-fronted Geese (Anser albifrons).

Migrating Cranes (Grus grus).

... and several unexpected stuff, as these Short-eared Owls (Asio flammeus)!

As you can imagine, this has been just a little glimpse of how amazing can be just to go to Falsterbo, sit down and enjoy bird migration. You can see pretty much anything migrating there... except maybe for actual seabirds, which sadly have decreased a lot around the area since the building of the bridge that connects Copenhague and Malmö. Nonetheless, in a nice, very strong westerly winds, it is worth going to some coastal places in the northern parts of Scania, where you might be lucky and enjoy big numbers of several seabird species, including sometimes very good views.

On my very last day this season we went seawatching around Torekov headland, and we saw this amazing Black-browed Albatross (Thalassarche melanophrys) from Rammsjö!!!

Contrary, for instance, to the previous year (2016), from the beginning of the season it was noticeable the low density and bad growth of the reedbed, probably due to the cold and late spring that affected most of Scandinavia. This had also an apparent effect on the breeding birds, translated into late breeding of the local species, such as Eurasian Reed Warblers(Acrocephalus scirpaceus) with chicks fledging as far as late August, and also Reed Buntings (Emberiza schoeniclus) with fledglings during mid-August, also slightly later than usual. The bad breeding season had direct effects on the seasonal totals, with the Penduline Tit(Remiz pendulinus) being a good example: only 4 individuals were ringed (average: 18), very likely as a consequence of the bad breeding season in Southern Sweden (Peter Öhrström com.pers.). But this effect is also seen in the numbers of Reed Warblers (A.scirpaceus) and Willow Warblers(Phylloscopus trochilus), species in which the juvenile peak migration, which is usually very strong and produces a lot of captures, was very diluted in numbers and almost unnoticeable through the season.

During the first days of the season in late July and most of August, the weather has been quite unpredictable, with almost daily rain showers and several windy days that probably lowered slightly the amount of trapped birds through the season.

In order, the most common species this season have been Reed Warbler(Acrocephalus scirpaceus) with 1061 individuals ringed, Sedge Warbler(Acrocephalus schoenobaenus) with 750, Reed Bunting(Emberiza schoeniclus) with 202, Barn Swallow(Hirundo rustica) with 180, Willow Warbler(Phylloscopus trochilus) with 149 and Sand Martin(Riparia riparia) with 143.

As it is already a clear trend in the last years of the standardised ringing at Flommen, Reed Warblers keep a clear tendency below the average (seasonal total: 1061, average: 1940), as well as Willow Warblers (seasonal total: 149, average: 628). As it was mentioned above, the apparent bad breeding season for this species has clearly affected this season’s numbers, especially in the case of the Willow Warbler. Due to the late breeding season, the adult peak migration passage for the common Acrocephalus Warblers, Reed Warbler(A.scirpaceus) and Sedge Warbler(A.schoenobaenus), has also been slightly delayed. On these species, adults migrate first than the juveniles, and some years the peak passage of adults has apparently already passed by the time the season starts the 21st of July. That is especially the case of the Sedge Warbler, and this year’s late breeding is clearly reflected in the big amount of adults trapped in the beginning of the season. The seasonal total for the Sedge Warbler is 750 ringed individuals, above the average reference number of 588, probably due to the unusual amount of adults. On the other hand, the numbers of Marsh Warbler (Acrocephalus palustris) were quite low this season, both for adults and first-years (seasonal total: 68, average: 92).

Juvenile (left) and adult (right) Reed Warblers.

The absence of Blue Tit (Cyanistes caeruleus) invasion this year is also affecting the seasonal total number at Flommen, since 4 birds were ringed when the average is 80. After the relatively calm August due to few juveniles (bad breeding season), September had very few good days in terms of amount of nocturnal migrants landing in the peninsula, and thus the numbers of the regular September species were generally lower than the average reference number. As examples: Robin(Erithacus rubecula) (seasonal total: 56, average: 75), Dunnock(Prunella modularis) (seasonal total: 25, average: 54) and Winter Wren(Troglodytes troglodytes) (seasonal total: 43, average: 40).

On the other hand, it is worth mentioning the good numbers for Barn Swallow(Hirundo rustica) (seasonal total: 180, average: 140), Sand Martin(Riparia riparia) (seasonal total: 143, average: 43) and White Wagtail(Motacilla alba) (seasonal total: 22, average: 12); three species which their numbers depend quite much on the formation of a roosting site in the study area, that was present this year daily during the beginning of the season.

Other typical migrants ringed at the Flommen reedbeds showed good numbers compared to the average 1980-2009, such as Tree Pipit (Anthus trivialis) (seasonal total: 33, average: 25), Common Whitethroat(Sylvia communis) (seasonal total: 37, average: 34), Red-backed Shrike(Lanius collurio) (seasonal total: 11, average: 8), Whinchat (Saxicola rubetra) (seasonal total: 51, average: 51) and Reed Bunting(Emberiza schoeniclus) (seasonal total: 202, average: 212). The case with the Chiffchaffs(Phylloscopus collybita) is interesting: the species has increased a lot the recent years and it is now far over the average (seasonal total: 98, average: 14).

Interesting local breeding birds such as Bearded Reedlings(Panurus biarmicus) bred again in the area (they were common breeding species in the past, but had disappeared for several years until they returned in 2015), and at least 2 pairs were detected. From the ringing data we obtained, both females in both pairs had a successful second clutch in August. In total, 13 juveniles were ringed through the season. Interestingly, at least two female Marsh Warblers(Acrocephalus palustris) were caught in the beginning of the season with broodpatches, and afterwards some fledglings confirmed the breeding of at least 2 pairs in the northern part of the reedbeds. Water Rails(Rallus aquaticus), as many other species as mentioned above, had also a delayed breeding season. 18 individuals were ringed at Flommen, 2 in the standardised ringing and 16 in extra ringing, using metal cages. During the last few seasons there has been an extra effort to ring local breeding Water Rails with quite good results, and although more work is needed, it is interesting to mention that we have no data corresponding to any returning individual (adult or juvenile) to the breeding sites.

Six foreign recoveries were caught during the season, two Sedge Warblers – one from Latvia and the other from France -, and 4 Reed Warblers – one from France, two from Belgium and 1 from Denmark. 27 individuals were caught from other ringing stations in Sweden: 11 Reed Warblers, 6 Sedge Warblers, 4 Barn Swallows, 4 Penduline Tits, 1 Sand Martin and 1 Reed Bunting.

Among the rare or scarcely captured species this season, there was the 6thSavi’s Warbler(Locustella luscinioides) ringed for the Bird Observatory (5th at Flommen), the first ever Firecrest (Regulus ignicapilla) to be ringed at Flommen (consequence of the increasing tendency of the species in Southern Sweden), a Great Reed Warbler(Acrocephalus arundinaceus) (58th at Flommen since 1980), a Bluethroat(Luscinia svecica) (51st at Flommen since 1980), a Wryneck(Jynx torquilla) (29th in standardised ringing at Flommen since 1980), 2 Common Grasshopper Warblers(Locustella naevia), 2 Jack Snipes (Lymnocryptes minimus) (12th and 13th in standardised ringing at Flommen) and 9 Spotted Crakes(Porzana porzana) (2 in the standardised ringing and 7 more in extra ringing in the area).

Ringers that worked on the reedbed with me were, listed by arrival date: Timmy Micallef, Per Andell, Ingela Källén, Emil Lundahl, Alex Zackrisson, Tore Dahlberg and Harald Ris. And, of course, big TACK to the rest of the Falsterbo Bird Observatory crew for another great season!